MoOn our walk this morning we found 2 big white mushrooms, not yet open, with pink gills inside.
After carrying them home they are stained with yellow fingerprints. Is there anything they could be except field muhrooms?
Any reliable websites for identifying the edible ones?

HelenQHi Mo - these sound like yellow stainers - don't eat them they are poisonous!They look v like field mushrooms, but the giveaway is that they rapidly stain yellow when bruised - hence the yellow fingerprints.If eaten they can cause sweats,flushing and severe stomach cramps in some people.Info paraphrased from Roger Philillips photographic guide to common and important mushrooms.I recognised your description straight away because we too picked some of these thinking they were field mushrooms, noticed the yellow stains and looked them up - what a disappointment!

This is what it says.
The Horse Mushroom, Agaricus arvensis Be careful of confusing it with the Yellow Stainer, Agaricus xanthoderma. This one smells strongly of iodoform or ink, not aniseed and its flesh (when cut) stains strongly yellow. The Horse Mushroom will only go yellow on the outside.

Mine smells of mushroom.

HelenQphew - sorry, didn't mean to alarm you!That info on smell's v useful - doesn't mention that in my book. I'll check out the website next time I find any interesting fungi